The Siemens SIRIUS 3RH1131-2UB40 is a size S00 auxiliary contactor with a 24 VDC coil, rated for 10 A at 24 V. It carries 3 normally-open instantaneous contacts and 1 normally-closed contact, with no leading, lagging, or make-before-break switching. The coil draws 3.2 W closing and holding power, with a built-in varistor surge suppressor.
The 10 A rating at 24 V is the thermal current for the auxiliary contacts — this governs the continuous current the contacts can carry in a control circuit, not a motor load. For higher voltages the rating derates: 6 A at 230 V, 3 A at 400 V, 2 A at 500 V, and 1 A at 690 V. The 1 A rating at 110 V and 0.27 A at 220 V are for DC switching, which is significantly lower due to arc extinction limits.
Panel integration
The screw and snap-on fastening method allows tool-free installation on a 35 mm rail. The S00 contactor size is the smallest Siemens frame, so it occupies minimal panel space.